1. Field of Invention
The invention relates to an ink composition, an ink set and an image formation method.
2. Description of the Related Art
In view of recent demand for high-speed printing, an ink jet recording apparatus equipped with a line head, which includes a large number of nozzles formed in lines such that the width of the line head is the same as the width of a sheet of a certain size, has been proposed.
In a liquid jetting apparatus including a line head, the head does not perform scanning. Therefore, if some of the large number of nozzles arranged in lines are clogged, it is not possible to perform supplemental printing with other nozzles that are not clogged. Accordingly, in such a liquid jetting device having a line head, there is demand for ink that causes less nozzle clogging, as well as need for new countermeasures for preventing nozzle clogging.
In this regard, a water-based ink which provides excellent image clarity and excellent print density, which contains a water-insoluble polymer containing a pigment, and in which the content of free polymer derived from the water-insoluble polymer is 0.40% by weight or less, has been disclosed (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2009-084501).
Furthermore, an aqueous dispersion for inkjet recording which contains a water-insoluble organic compound and crosslinked water-insoluble polymer particles containing a colorant has been disclosed as a water-based ink having excellent glossiness and excellent storage stability (see, for example, JP-A No. 2007-314784). In the water dispersion, the crosslinked water-insoluble polymer particles are obtained by crosslinking a water-insoluble polymer using a crosslinking agent.